Electrical and optic connectors commonly include an insert with a plurality of parallel contact-receiving passages, with the insert received in a shell. The insert is commonly inserted forwardly into an open rear of the shell, and is held therein by any of a number of devices, including screws and sidewardly-slideable retainer plates. A simple means for retaining an insert in a shell, which facilitated removal of the insulator from the shell when necessary, would be of value.